System and method for flush-triggered imaging

Abstract

The invention generally relates to intravascular imaging and methods of improved image quality by triggering image operations with a vessel flush. The invention provides systems and methods for intravascular imaging in which a flush such as the influx of clear saline or radiopaque dye triggers the imaging operation. The flush is detected by a mechanism—such as a pressure sensor or optical device on the imaging catheter, an external angiography system, or other device—that uses detection as a trigger to initiate imaging. Thus, when the blood is flushed, the catheter automatically takes a picture of the vessel wall.

What is claimed is: 
     
         1 . A method of intravascular imaging, the method comprising:
 positioning a distal end of an imaging catheter within a blood vessel and immersed in blood, wherein a proximal end of the catheter is connected to an imaging system;   providing an influx of a solution to flush the blood from the vessel;   detecting the influx; and   using the detection of the influx of the solution to trigger an imaging operation with the imaging catheter.   
     
     
         2 . The method of  claim 1 , wherein the influx is detected from within the vessel. 
     
     
         3 . The method of  claim 1 , wherein the influx is detected within the vessel from outside of the patient's body. 
     
     
         4 . The method of  claim 1 , wherein the imaging system is an OCT system. 
     
     
         5 . The method of  claim 1 , wherein the imaging system is an IVUS system. 
     
     
         6 . The method of  claim 1 , wherein detecting the influx comprises detecting an optical change via OCT. 
     
     
         7 . The method of  claim 1 , wherein detecting the influx comprises detecting a pressure change via a pressure sensor on an IVUS catheter. 
     
     
         8 . The method of  claim 1 , wherein detecting the influx comprises detecting a change on an angiogram. 
     
     
         9 . The method of  claim 1 , wherein the imaging operation comprises a pullback. 
     
     
         10 . The method of  claim 1 , wherein the imaging system is configured to initiate a catheter pullback automatically and in direct response to the detection of the influx. 
     
     
         11 . A system for intravascular imaging, the system comprising:
 an imaging instrument;   a catheter comprising a proximal end connected to the imaging instrument and a distal end configured for insertion into a blood vessel of a patient;   a lumen extending along the catheter for delivery of a solution to flush blood from the blood vessel; and   a sensor to detect an influx of the solution, wherein the system is configured to use the detection of the influx of the solution to trigger an imaging operation with the imaging catheter.   
     
     
         12 . The system of  claim 11 , wherein the influx is detected from within the vessel. 
     
     
         13 . The system of  claim 11 , wherein the influx is detected within the vessel from outside of the patient's body. 
     
     
         14 . The system of  claim 11 , wherein the imaging instrument comprises an OCT device. 
     
     
         15 . The system of  claim 11 , wherein the imaging instrument comprises an IVUS device. 
     
     
         16 . The system of  claim 11 , wherein detecting the influx comprises detecting an optical change via OCT. 
     
     
         17 . The system of  claim 11 , wherein the catheter further comprises a pressure sensor operable to detect the influx. 
     
     
         18 . The system of  claim 11 , further comprising an angiography device operable to detect the influx. 
     
     
         19 . The system of  claim 11 , wherein the imaging operation comprises a pullback. 
     
     
         20 . The system of  claim 11 , wherein the imaging instrument is configured to initiate a catheter pullback automatically and in direct response to the detection of the influx.